Question

In a class test (+ 3) marks are given for every correct answer and (–2) marks are given for every incorrect answer and no marks for not attempting any question. Radhika scored 20 marks. If she has got 12 correct answers, how many questions has she attempted incorrectly?

Answer 1

8 questions she should attempt wrong

Answer 2

✳️ Solution: for the given situation we can assume that the number of correct answers Radhika attempted are x

and incorrect answers are y

to represent the situation we can convert the situation into a linear equation of two unknown

$3x - 2y = 20$

if correct answers are given as 12 so we can put x = 12

$3(12) - 2y = 20 \\ \\ 36 - 2y = 20 \\ \\ - 2y = 20 - 36 \\ \\ - 2y = - 16\\ \\ y = \frac{16}{2} \\ \\ y = 8$
by this way we had calculated that Radhika attempted 8 wrong answers.